To trace the origins of the Spanish colonial society that later became the Republic of Colombia, we must return to the opening decades of the sixteenth century, when Spaniards ranged along the coast between Cabo de la Vela and the Isthmus of Panama, searching for gold and slaves. Experiments in permanent settlement on these mainland shores started early. Alonso de Ojeda founded the first colony in Colombian territory at San Sebastián de Urabá in 1510, after his raids in the Cartagena region had been repelled by belligerent local tribes. Further Indian hostility, again provoked by Spanish slaving raids, forced another move west, to Darién, where the Spaniards founded a new base at Santa María de la Antigua. Again, the colony was short-lived. Stricken by disease, the local Indians became incapable of supporting the Europeans' parasitic community, and in 1524 Santa María de la Antigua was abandoned. Yet again, the Spaniards moved west, this time to Panama, which, as Castilla del Oro (“Golden Castile”), became a fresh focus for Spanish activity. Then, in 1526, other Spaniards created another, quite distinct base in Colombian territory, at the eastern end of the Caribbean coast: by founding Santa Marta, they opened what was to become a crucial frontier for conquest in Colombia's interior.